Only possible with the existence of "billionaires".
None of this was done in a vacuum of billionaire self funding.
A vacuum of billionaire self funding? Of course not, but would these ventures have progressed to where they are without the deep pockets of some of these billionaires?
People mock him for being bad at estimating how long projects will take… but even if you agree with the critics, he's still the one-eyed in the land of the blind when it comes to space mission project planning.
Fair, I've heard the same from chatting with someone who shall not be named who got on a different list.
I can't remember if it was them or someone else who said that people lie about their wealth all the time for lists like these; the show-offs who want on them and pretend to have more, and the quiet ones who want off them and pretend to have less. (The person previously mentioned was one of the quiet ones).